Condensate pump and control means



April 25, 1961 F. N. zlMMERMANN ETAL 2,981,196

CONDENSATE PUMP AND CONTROL MEANS Filed April 27, l959 5 Sheets-Sheet l April 25, 1961 F. N. z|MMERMANN ETAL 2,981,196

CONDENSATE PUMP AND CONTROL MEANS Filed April 27, 1959 3 Sheets-Sheet 2 April 25, 1961 F. N. ZIMMERMANN ETAL 2,981,196

CONDENSATE PUMP AND CONTROL MEANS Filed April 27, 1959 5 Sheets-Sheet 3 if @af/Ma@ 'United CONDENSATE PUMP AND 'CUNTROL MEANS Fried Apr. 27, 1959, ser. No. 809,263 4 Claims. (ci. 10s- 26) The present invention pertains to a novel pump and -control means designed particularly for draining purposes, but also capable of service for the general purposes of elevating water and other liquids.

It is amongl the objects of this invention to provide an electrically driven pump with electric motor, the hydraulic pumping elements, and the oat control mechanism embraced in the same housing, the lower portion of the housing constructed in such a manner that it can be submerged in Water such as found in a drip pan beneath an air conditioning apparatus, or the like, whereby the pump will run for a period of time at high eifrciency, without trouble or care until the drip pan, or the like, is vsubstantially dry.

lIn our U.S. Patent 2,829,598, issued April 8, 1958, we described and claimed a Condensate Pump and Controls where the iioat control mechanism was enclosed within a separate enclosure. The present invention relates to a dilterent type housing for enclosing all the units and effected by cooling means, for accomplishing new and novel results.

Accordingly, this invention relates to a pump of the refer-red to class, a construction and arrangement which is more efflicient than corresponding pumps now in use.

A particular object of this invention is to provide an ecient combination unitary housing and cover assembled in spaced relation therewith, allowing air to be circulated in and around the motor within the housing by a fan assembled upon the upper end of the motor shaft.

Another object of this invention is to provide in a portable pump having7 a centrifugal impeller, means whereby the friction load of the iluid is materially reduced with reference to pumps of the same general type.

Another object of this invention is to provide, a portable pump housing with a pump mounted with its pump shaft arranged vertical-ly, and embodying a fan cooling means at its upper end to draw air inwardly and outwardly over the motor so as to cool yand prevent fluid from accumulating on or near the motor, and with an impeller on its lower end having radially and horizontally disposed blades to raise the water into the impeller chamber and thence upwardly and outwardly through the outlet pipe.

Another object of this invention is to provide a portable pumping unit comprising a plastic pump housing, W-ith motor, pump and oat control means assembled therein where the parts are closely coupled and in which the whole of the instrumentality is of low height and small mass, whereby it will tit conveniently into very tight drip pan locations and providing adjustable legs for positioning in drip pans having an irregular shape and angu'larly arranged floors.

Another object of this invention improve upon the condensate pumps of earlier inventions Where the pump housings are partially submerged under water and the rates Patent G or when the pan is substantially dry, running twenty-four (24).hou rs a day, or until manually stopped. Said 2,981,196 Patented Apr. 25, 1961 earlier type pump thereby functions for hours when it is not necessary, since an average pump will maintain a drip pan substantially dry seventy percent o-f the time. This novel pump is automatically controlled, does not run continuously unless necessary and being air cooled will run for a greater period of time without repair.

Another object of the invention is to provide a pump construction and method of pumping water and other liquids, wherein both the driving motor, and pump impeller may be correctly centered in vertical alignment within the pump housing constructed of plastic material and wherein the impeller may be properly borne and suspended within the pump chamber and supported both axially and radially with such accuracy by the unitary plastic housing to obviate outboard bearings, luniversal joints or loose couplings between the motor and impeller.

Another object of this invention is to provide a portable pump of the class described with a more efficient eal for preventing iiuid being forced and/or from seeping into the motor chamber; the lower motor thrust bearing casing resting upon an annular resilient seal sleeving the upper portion ofthe impeller shaft.

And still another object of this invention is to provide a' portable rotary pump handling a substantial volume of water and having a natural tendency to create a circular motion of the body of water in which the pump is partially submerged, mixing air with water, and includ ing air-bleed passageway/s to eiiectively prevent, check, or relieve air locks within the entire impeller cavity. By the present invention, air-bleed passageways are provided within a partition separating the interior of the pump housing into an impeller cavity on one side thereof and a motor chamber on the other side thereof; the small airbleed passageways and larger channels forming a manifold type channel between the low pressure areas of the impeller cavity and the exterior of the pump housing, which electively relieves, checks, or prevents the formation of an air lock within the impeller cavity and annular bore about the impeller shaft.

Accordingly, a primary object of this invention is to provide a novel condensate pump free of a-ir locks and with a control float means, all arranged within a unitary pump housing with end plate and cover and adapted to run intermittently as desired to empty a`sump, a drip pan, or the like, to substantial dryness.

An additional object of the present invention is ,to provide a method of making, assembling and cooling a portable pump for carrying out some, or all, of the preceding objects and more particularly to provide a method of locating a planetary air-bleed system, locating and aligning the motor and impeller parts of a pump with respect to their respective working chambers and cooperating parts, housing, float mechanism, and instrumentalities.

Other objects include providing method and means for making an etlicient, compact, longlived, rugged rotary pump economically and eir'ectively.

Other objects and features of the invention will be Set `forth more fully hereinafter.

The full nature of the invention will be understood from the accompanying drawings and the following description.

In the drawings:

Figure 1 is a fragmentary View in side elevation, par- -tially broken away and in section, illustrating the portable condensate pumping unit and control means of this invention in operative relation to a drip pan beneath an evaporator, or an air conditioning apparatus shown in phantom by dotted lines, from which liquid is to be pumped when it accumulates in the pan to an undesirable depth;

Figure 2 is an end view of the condensa-te pump housforming the base wall Vshown in the other figures, showing the iioat upon the float shaft, and showing the cover of the impeller chamber broken away to show the impeller assembled upony the impeller shaft within 4the impeller chamber;

Figure 7 is `an enlarged fragmentary view as shown in Figure 4, showing the motor bearing housing resting upon the `annular resilient seal about the impeller shaft, and further showing the air-bleed manifold system in the Vpump;

Figure 8 isa top plan view of the pump housing Without the cover or end plate assembled therewith, and all cooperating parts of the pump removed therefrom;

Figure 9 is a sectional View of the pump housing taken substantially on line 9 9 of Figure 8; and

Figure 10 is an exploded View in perspective of two annular sealing means .and the impeller as used and arranged With the pump of this invention.

Referring to the drawings, the reference numeral designates a suitable, conventional illustrated drip pan, or reservoir, or the like, beneath the evaporator 16 shown dotted, in which a small quantity of liquid 17 is shown; as more liquid is collected it is to be removed from the drip pan 15 by the condensate pump, or unit 19, when `partially immersed in said liquid and float raised thereby.

Referring to Figures 2 through 7, wherein details of the construction of the pumping unit 19 are illustrated, the pumping unit consists of a pump housing 20 constructed from a suitable plastic, embodying .a front wall 21, a rear wail 22, one end wall 23, an integrally connected inner wall arranged transversely and between said front, rear tand end walls dividing said housing 20 into an irnpeller chamber 26, a motor cham-ber 27, a oat chamber 2S and switch control chamber 29. A plastic end plate is secured to the end of said housing opposite said wall 23 by screws 31 in threaded bores 13, shown by Figure 5. An integral cylindrical hub portion 32 is formed with said end wall 23 and extends angularly and upwardly therefrom. Said hub portion 32 being bored out to form an interior opening 33 leading into the impeller cavity 26, and forming an exterior opening 34. The opening 34 is provided with threads 35 to receive a pipe fitting 37 ladapted to retain a suitable hose, iron pipe, or copper tubing 3S.

The integral plastic wall 25 embodies a vertical partition intermediate the ends of said housing 20, a horizontal top shelf member 41 and horizontal bottom shelf member 42 extending longitudinally therefrom to-l ward the open end of said housing, a horizontal shelf 43 extending longitudinally toward the closed end of said housing, said shelf being substantially mid-way between the upper and lower edge portions o-f said housing, said shelf 43 formed with a depending wall 44 forming with the front, rear, and end walls a sump 45 and lower most portion of the motor chamber 46, the upper portion of said chamber 46 enclosed by front wall 21, rear wall 2, end wall 23 and partition 40. The bottom end of said depending wall 44 turns and extends horizontally and longitudinally towards the closed end of the housing 3, said wall 4S being a common wall forming the base of said sump 45 of motor chamber 46 land forming the top wall of the impe-ller chamber 26. An annular wall 5d is integrally formed with and dependving from said wall 4d and forming the circular side wall of said impeller chamber 26. Said impeller chamber 26 lis closed'by a bottom plate SZ'to form the enclosed fimpeiler cavity. Said plate 52 is secured to the bottom of said wall 50 by thread screws 53 extending into threaded bores 54; shown by Figure 6. Said plate 52 is provided with a central opening 55 for the entry of liquid 17 into the impeller chamber 26; shown by Figures 4 and 7. The upper portion of said housing 20 is covered by a rectangular shaped cover 6i? with depending walls 61, said cover is larger than the rectangular upper portion of said housing so that the depending walls 61 extend outwardly from the vertical walls of said housing providing air space 62; clearly shown by Figure 4. The corner portions of said cover 60 are provided with vertical counter sunk openings through which thread screws extend and secure the cover to threaded bores 63 in the upper corner portions of said housing, shown by Figure 5. The lower portion of said housing 20 is formed with cylindrical vertical leg member 64 arranged in the corner potions thereof. Said members 64 embody threaded bored openings 65 to receive .adjustable bolts, the heads 66 of said bolts supporting the entire pump 19 in the drip pan 15 whereby the bolt heads 66 elevate the bottom plate 52 a desired distance above the bottom of said drip pan 15.

Referring to Figures 4, 5 and 7, the motor chamber 27 is shown enclosing an electric motor 70 having a rotor 71 rotatable on .a vertical axis and driving shaft 72. it will be noted that the motor has the' -eld coils 73 mounted to one side of the rotor 71, and above shelf 43. Said base wall 43 is provided with a cylindrical opening to loosely receive the lower end portion of shaft 72, allowing the lower end of the shaft to extend into the impeller cavity 26. The impeller S0 is attached to the lower end of said shaft 72 by screw S5, and driven thereby, is disposed in the impeller chamber, or cavity Z6. An annular washer, or grommet 81, with cylindrical opening is assembled with a rubber covered shaft seal 82. and positioned upon said shaft 72, whereby the grommet 81 and seal 82 rest upon the upper Surface of wall 4S about the opening 75. The bearing cap 76 of motor 70, shown in Figure 4, rests upon the top annular surface of said grommet S1, said grommet 81 and said seal 82 sealing the opening 75 around shaft 72 between the sump 45 in motor chamber 46 and said iinpeller cavity 26, preventing any liquid from entering said motor chamber. The upper end of the. driving shaft 72 extends through bearing cap 77 and has a fan 78 secured to the free end thereof by a suitable means. The blades 79 of the fan 78 are in the form of vertically disposed curved vanes extending horizontally outwardly from said shaft 72 to circulate the air within the motor chamber 46; cool air being drawn in and forced outwardly between the closure 60 and top of the chamber walls through opening 62. The bearing caps 76 and 77 are secured to a spider type bracket 74 secured to the casing of the motor land is secured as by bolts 68, the threaded lower ends of the boits 68 extending into threaded bores 83 arranged in base wall 43. A screw extends through the motor casing and is secured in threaded bore 91 in base wall 48, shown in Figures 5, 8 and 9.

The base Wall 48v is provided with plastic reinforcing ribs and a circular hub portion 87 with an annular groove, or channel 86, shown in Figure 8. It will be observed that the wall 48 below said channel 86 is provided with four small vertical air-bleed passageways 100, 101, 102, 103. The grommet 81 and shaft seal close the upper portion of said channel 86, forming a circular cavity 104. An air bleed channel extends from an opening 106 in the outside of said pump housing Z0 straight through said base wall 48 to said channel 86, said air bleed channel 105 is arranged centrally and longitudinally of the housing and in a plane arranged five degrees from the horizontal. The hub portion 96 formed by cylindrical opening 75 and channel 86-is provided with air bleed channel 108;` said channel 108` being in valignment with f channel-106mm formed by the Y same 'drilling operation,

the drill entering the side wall 23 forming opening 106, extending through wall 48 forming opening 107 in wall of channel 86, and extending through the hub portion 96 forming the two air bleed channels 108 in the hub portion 96. These air bleed channels 105 and 108 form direct communication -with the circular channel 8'6 and cylindrical opening 75 about shaft 72, whereby all air in pockets about the shaft in the impeller chamber 26, or areas thereabout, is completely removed, the air being forced out of opening 106.

The pump control unit is substantially enclosed in chambers 28 and 29, closed by plastic plate 30 secured thereto by screws 31. A plastic hub 110 is formed on the vertical partition 40 and extending horizontally into said switch control chamber 29. A switch arm 111 is pivotally mounted upon said hub 110 by pivot bolt 112 screwed into said hub 110. Said arm 111` is composed of a vertical body portion 113, an intermediate extending vertical arm portion 114 and a horizontal free end portion 115, said free end 115 having an aperture 116 therein to allow a vertical float rod 11,7 to pass freely therethrough; said rod 117 having an annular oat 118 secured at the lower free end thereof. Said rod 117 extends vertically and is guided through opening 119' in shelf 42 and opening 160i in shelf 41. The float 118 is generally a hollow metal float, however in this particular instance the float 118 is an annular disc of Styrafoam, the guide rod 117 suitably secured therethrough. Intermediate the ends of said rod 117 are properly spaced two retaining rings, a lower ring 120 and an upper ring 121. Said rings may be referred to as float stops secured to said rod 117, whereby the free end 115 of the arm 111 alternately engages said rings during the travel of said rod upwardly and downwardly. The float is intended to ride upon the surface of the liquid body of water in the drip pan 15. The intermediate portion 114 of arm 111 is provided with a clip 124 to carry a mercury switch 125. In the normal lower position of the float, as shown by Figure 2, the mercury switch 125 is arranged to be in open position. As soon as the liquid level in the drip pan 15 rises above the specified height, the oat 118 rises with such liquid and the rod `117 moves upwardly causing ring 120 to engage the free end 115 of arm 111, said arm will tilt about the pivot bolt 112 causing the mercury in the switch to close the contacts therein and the motor circuit, thus establishing pump operation. When the float rod 117 drops due to lowering of the oat, the ring 121 contacts the upper surface of arm end 115, tilting said arm 11 downwardly, causing the mercury to open the contacts and the motor circuit. In this way the `action is automatic, the float and the mercury switch yclosing and alternately opening the cirl cuit to the motor 70 and as a consequence maintaining a substantially dry condition in the drip pan 15. The electric current circuit is clearly shown by Figures 2, 3 and 5, line 130 is secured to the terminal block 128 by screw 129 where it is joined by line 1321 connected to the motor 70; line 13-5- is secured to the terminal block 147 by screw 133- where it is joined by line 134 connected to the mercury switch 125; return line 137 leading from the mercury switch is secured to the terminal block by screw 138 where it is joined by a line 139` connected to the motor 70. The flexible cord 142 embodying lines 130 and 135 extend through an opening 140 in the plastic end plate 30 into chamber 29. The lines 130, 13S, 134 and 137 extend from chamber 29 through a transverse rectangular shaped opening 145 in shelf 41, to the Various connections as described above. The terminal block 147 is an integral part of shelf 41 and is divided into four separate compartments 150, 151, 152 and 153 by suitable vertical ribs. The compartments separate the metallic connections on the ends of the electric current carrying line preventing short circuit of the same.

The impeller cavity 26 is closed except for openings 33` and 55. Water enters the impeller cavity 26 through `rod is then passed through aperture 116 in free arm end 115, ring 121 is then placed upon the rod 117, and the upper end of rod 117 is then passed through opening 160`in shelf 41; the proper positioning of rings 120 and 121 regulates the proper functioning of said mercury switch and in turn the proper operation of the pump. The shaft seal 82, is a substantially rigid member, it can be made of metal and covered with rubber to resiliently sleeve the shaft 72. The pressure of the thrust bearing cap upon the grommet 81 presses the grommet tightly upon the upper surface of wall 48 and into tight engagement with the shaft seal 82; thereby closing the upper open portion of channel 86 making it a closed air-bleed cavity. The air bleed channels 1051 and 108 extending from the area about said shaftv 72 to the exterior in a slight upwardly and outwardly manner prevents air-locks any place between the impeller chamber 26 and exterior opening 106.

The terms and expressions which have been herein employed are used as terms of description and not limitation, and there is no intention, in the use of such terms and expres-sions, of excluding any equivalents of the features shown and described. YIt is recognized that various modifications are possible within the scope of the invention claimed.

Having thus described this invention, what we claim as new and desire to secure by Letters Patent is:

l. A portable electric water condensate pump, comprising: a unitary supporting housing and a housing cover, said housing being of rectangular configuration in a horizontal plane, said housing having a pumping chamber, a motor chamber, a iioat chamber, a switch chamber therein; said housing having a closure assembled therewith and spaced slightly therefrom forming an air passageway, said pumping chamber provided with a liquid inlet and a liquid outlet; the base portion of said housing adapted to be immersed, at least in part, in a supply of liquid to be pumped; said housing cover being wider and longer than said supporting housing, said motor charnber being open to the atmosphere effected by the perimeter of the housing cover being spaced at a distance from the entire peripheral edge portion of said supporting housing, a motor with a lower bearing cap supported within said motor chamber, a vertical shaft assembled with said motor, said motor for driving said vertical shaft extending vertically through the body of the housing and connected to the motor; a fan mounted on the upper end of said shaft and rotatable therewith to circulate the air within the motor chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; said pumping chamber having an upper wall; a manifold-type air bleed passage including an annular channel arranged within said upper wall; an annular grommet and a shaft seal assembled upon said shaft above and in contact with the upper surface of said upper wall, said lower bearing cap resting upon the top annular surface of said grommet exerting pressure on said grommet and sealing the open upper portion of said annular channel, the proximal end of said air-bleed passage in communication with said pumping chamber; the distal end of said air-bleed passage open to the atmosphere, allowing entrapped air within the pumping chamber to escape; said motor chamber and said pumping chamber in one end of said housing; said float chamber and said switch chamber arranged one above the other in the opposite end of said housing, a first shelf horizontally formed between said oat chamber and said switch chamber, said of said second shelf, a circuit embodying a normally open switch connected to said terminal block and fromV there to said motor; said switch supported by said arm bracket; means upon said rod for controlling the action of said arm; said switch closed when said float and said rod are elevated incident to rising liquid in the float chamber as said rod elevates one end of said arm supporting -said switch, and said switch opening when the oat and rod lower incident to declining level of liquid in the float chamber; whereby water is pumped out of said pump chamber by said impeller and air is circulated within said motor housing by said fan when said switch closes said circuit.

2. A portable electric condensate pump according to claim 1 wherein said manifold-type airbleed passage comprises an annular channel; a plurality of vertical airbleed passages connecting said annular channel with the pumping chamber; and a longitudinal air-bleed passage joining said annular channel with the annular space about the vertical shaft in the upper wall of said pumping chamber with the atmosphere.

3. In a device of the kind described for use with a drip pan for collecting and holding a body of water concentrate; a portable pump for discharging water concentrate from any drip pan in order to obtain a substantially dry condition within said pan; said pump comprising a housing and housing cover, said housing having a pumping chamber, a motor chamber, a switch chamber and a float chamber; said motor chamber being located above said pumping chamber and arranged in one end of said housing; said switch chamber arranged above said oat chamber at the opposite end of said housing; said iloat chamber open at its lower end and substantially closed by a shelf at its upper end which forms the base of said switch chamber; a second shelf substantially closing said switch chamber at its upper end; a motor supported within said motor chamber, a vertical impeller shaft depending from said motor, said motor for driving said vertical impeller shaft extending downwardly therefrom and extending into said pump chamber; said housing cover being wider and longer than said supporting housing, said motor chamber being open to the atmosphere effected by the perimeter of the housing cover being spaced at a distance from the entire top peripheral edge portion of said supporting housing, an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; a movable float and vertical supporting rod arranged within said iloat chamber, vertically aligned openings in said shelves, said rod extending upwardly through said vertically aligned opening in the first and second shelf; stop means assembled upon said rod within said switch chamber for controlling an armtype lever pivotally mounted upon an integral hub formed on the transverse vertical wall of said switch chamber; a circuit embodying normally open mercury switch connected to said motor; said switch supported upon said arm-type lever; one end of said arm-type lever and said switch being moved upwardly to close the switch when said oat and rod are elevated incident to rising liquid in said reservoir and surrounding the base of said housing, said switch again becoming open when the iloat and rod lower incident to the declining level of liquid around said housing; and a fan connected to the upper end of said impeller shaft and rotatable therewith above said motor in said motor chamber; whereby the air is circulated and the motor cooled by said air when said switch is closed in said circuit.

4. A portable electric water condensate pump comprising, in combination, a one piece supporting housing having detachably secured therewith one housing end wall and a housing cover, said housing having an integral, substantially rectangular transverse bottom wall located a distance above the lower extremities thereof, said detachable housing end wall being of rectangular conguration, said detachable housing cover being wider and longer than said supporting housing and rectangular in shape with depending flanges spaced at a distance from the top peripheral edges of said supporting housing and said detachable end wall to provide an air passage space therearound, said supporting housing having a pumping Vchamber located in the closed end portion thereof and arranged beneath said transverse bottom wall thereof, a motor chamber located within the closed end portion of said supporting housing above the bottom wall and directly above said pumping chamber, said pumping chamber having an integral vertical cylindrical side wall with a detachable circular bottom cover having a central aperture providing a water condensate inlet, a water condensate outlet formed in one side of said cylindrical side wall, the base portion of said housing adapted to be immersed, at least in part, in a supply of water condensate to be pumped, a motor supported within said motor chamber, a vertical impeller shaft depending from said motor and extending downwardly therefrom and into said pump chamber through anopening in said bottom wall, an impeller mounted on the lower end of said shaft in said pumping chamber and rotatably driven by said motor, a float chamber located in the opposite end of said supporting housing from the end embodying said pumping chamber and arranged below said bottom wall thereof, an integral vertical partition formed with said bottom wall and arranged intermediate the ends of said supporting housing, an integral top shelf member horizontally formed with the upper portion of said vertical partition forming a switch chamber C-shaped in longitudinal cross-section and closed by said detachable end wall and the side walls of said housing, said switch chamber located directly above said oat chamber and having apertures centrally arranged in said top shelf and the bottom wall embodied therewith and said apertures vertically aligned with each other, a fioat and guide rod within said float chamber with the upper end portion of said rod extending through said apertures and through said switch chamber, the vertically aligned openings per- Amitting vertical movement of said float and rod, a normally open mercury switch pivotally connected by means of an arm to said vertical partition of said switch chamber, said switch combined with a circuit connected with said motor, said mercury switch closed automatically when the float raises incident to rising water condensate in the oat chamber for controlling the action of said motor and impeller, and said switch opening automatically w-hen the float lowers incident to declining water condensate in the float chamber.

References Cited in the le of this patent UNITED STATES PATENTS 

